Laptops are no longer to be regarded as purely functional add-ons to your home network; they contain many features which will far exceed the expectations of most moderately savvy purchasers. Increased memory, speed and functionality have gone hand in hand with ever-smaller machines and falling prices; the time is right to buy.

Memory and speed.

The CPU - the computer's central processing unit - is a major factor in what governs the laptop's speed. Pentium manufacturers Intel have recently brought out the Centrino, a CPU which is specifically designed for portable computers and wireless internet access, although there are many which emulate its speed and capability.

Many good laptops come with Centrino chips as standard; worthy alternatives are the AMD Athlon range and the Mobile Pentium 4 or Celeron from Intel.

There are two types of memory, often called the hard drive and the RAM; think of the hard drive as the library in which the computer stores your pics, documents and music, and the RAM as how much it can concentrate on at once.

20Gb of hard drive memory is fine for pretty functional work; word processing, accounts, internet access, some music storage. As you get over 80Gb, you'll be able to store all of your music, video and high-resolution photos.

Many laptops come with 256Mb or more of RAM as standard; this is enough to watch video, listen to music, work and access the Web without too much trouble.

You can get cheap laptops with a small amount of RAM - 64Mb, for example - which will struggle with multimedia and complicated programs but which are good for simple work.

Operating system

Most computers come with the latest version of Windows - Microsoft's operating system, which enables you to interact with the computer - as standard. Until recently, XP was the most recent commercial version, the beginning of 2007 sees the launch of Vista.

A change in operating system means that, eventually, older systems tend to become outdated and less useful.

Think about exactly what you want your computer to do, then ask the sales advisor to let you know how the change in operating system will directly affect your use of the computer, after explaining what you'll need it for.

Other features

Modern computers tend to come with a wireless internet card (which enables you to connect to the Web without a direct link to a modem, from a hotspot in a cafe or on a train) and other devices like CD and DVD players and rewriters.

If you're given the choice, try to pick up a laptop with wireless capabilities, but think hard about whether or not you need the rewriting capabilities - particularly as the advent of Vista will impose restrictions on the copying of music.

Other factors to consider are weight and size and the screen clarity and dimensions. Do you want the laptop to be portable, or will it just sit on your desk?

Walk the sales advisor through your precise needs and they will help you accordingly.